臺灣博碩士論文加值系統

硫酸孕烯醇酮(pregnenolone sulfate；PS)是一種可在腦中自行合成的神經性類固醇，它可透過非基因的作用來調控神經細胞的興奮性，亦可增強實驗動物的學習與記憶能力。而癲癇是一種因中樞神經細胞過度興奮產生高度同步化放電現象所造成的疾病，當發作時會導致人體異常的活動功能或意識的喪失。有研究報告顯示在顳葉大腦海馬迴區域產生病變所造成的癲癇病患中，其學習與記憶能力較正常人差，但癲癇動物的學習與記憶能力是否也較正常動物差及PS對癲癇動物的學習與記憶能力是否也如對正常動物一樣具有增強的作用則不很清楚。在本研究中，我們以正常大白鼠及側腦室注射kainic acid所誘發的癲癇大白鼠為材料，探討癲癇大白鼠與正常大白鼠的學習與記憶能力是否有差異，同時，我們也研究側腦室注射PS對這二組動物的學習與記憶能力的影響作用。學習與記憶能力是利用被動逃避學習箱來測定，學習與記憶能力越好的大白鼠訓練後，由亮室跑入暗室的時間(retention latency)越長。結果顯示癲癇大白鼠的retention latency顯著比正常大白鼠短，表示癲癇大白鼠的學習與記憶能力較正常大白鼠差。藉由rotarod treadmills及電刺激敏感度的測試，可知癲癇大白鼠的reteneion latency之所以較短並不是因為其活動能力較好或是對電刺激較敏感所導致。此外，我們發現高劑量(840 pmol) PS的給予可顯著增強正常大白鼠的學習與記憶能力，但對癲癇大白鼠的學習與記憶能力卻無顯著增強作用，表示癲癇大白鼠對PS的敏感度較正常大白鼠為低。

The neurosteroid pregnenolone sulfate (PS) modulates neuronal excitability via a non-genomic mechanism. When administered intracerebroventricularly to experimental animals, PS also enhances post-training memory performance. Epilepsy is a disorder of brain function characterized by recurrent seizures that have a sudden onset and are evoked by over-activation of central neurons. During seizure, patients usually generate convulsive movement and sometimes lose consciousness. Memory deficits, particularly deficits of long-term memory, have often been reported in patients with temporal lobe epilepsy. However, whether memory deficits also occur in epileptic animals and whether PS has a memory-enhancing effect on epileptic animals are not clear. In the present study we explore the effect of intracerebroventriclularly injected kainic acid on rat learning processes by using the passive avoidance learning paradigms. In addition, we also study the effects of PS injected intracerebroventricularly on learning performance in normal and epileptic rats. The retention latency in epileptic rats is shorter than that in normal rats, indicating poorer memory performance in epileptic rats. Rotarod treadmills and electric shock sensitivity tests exclude the possibility that the shorter retention latency in epileptic rats is due to their higher motor activity and higher shock sensitivity. Furthermore, administration of high dose (840 pmol) of PS produces a memory-enhancing effect on normal rats but has no significant effect on epileptic rats, suggesting lower sensitivity to PS in epileptic rats.

中文摘要 I
英文摘要 II
緒論 1
材料與方法 4
結果 15
討論 35
參考文獻 38
附錄 42
誌謝 47
履歷 48
著作權聲明

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